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## Comment on

Sequence with k## Could you explain why we this

t10-t7 = t3

then set

tn = t3

36= 3^2 +3k

solve for K

k= 9

t25= 25^2 +9(25)

= 850

## We can't conclude that t10 -

We can't conclude that t10 - t7 = t3 (as you have done in the first step of your solution)

To see why this isn't necessarily true, consider this sequence where term_n = n²

term_1 = 1

term_2 = 4

term_3 = 9

term_4 = 16

term_5 = 25

term_6 = 36

term_7 = 49

term_8 = 64

term_9 = 91

term_10 = 100

Notice that term_3 = 9

Also notice that term_10 - term_7 = 100 - 49 = 51

As you can see, term_10 - term_7 does not equal term_3

Cheers,

Brent